The present invention relates to a braking device particularly for skates.
The problem of braking the wheels in order to adjust the speed of the skate is currently felt in conventional roller skates, whether constituted by a shoe associated with a support for two pairs of mutually parallel wheels or constituted by a shoe associated with a supporting frame for aligned wheels.
It is thus known to use adapted blocks or pads, usually made of rubber, which are placed at the toe or heel region of the shoe. When the user tilts the shoe forwards or backwards, the pad interacts with the ground and braking is thus achieved.
However, these solutions have drawbacks, as the user has to rotate the shoe, and therefore the frame associated thereto, at the toe or at the heel, and this can cause a loss of balance with consequent falls.
U.S. Pat. No. 1,402,010 discloses a roller skate having a band that can be fastened on the user's leg above the malleolar region, a rod being connected thereto.
The rod surrounds the rear of the leg and is curved so as to laterally affect the leg. An end of the rod is associated with a lever assembly, at the malleolar region, and the lever assembly is articulated to a structure protruding from the wheel supporting frame.
The lever assembly protrudes at the rear of the frame and is connected to a plate that is shaped approximately complementarily to the curvature of part of an underlying and facing wheel.
This embodiment has drawbacks: first of all, a relative motion occurs between the band and the leg during the sports practice, and this does not make its use comfortable due to the continuous rubbing of the band on the leg.
Furthermore, the plate is activated every time the user bends his leg backwards beyond a given angle, without true and easy possibility of varying this condition.
Furthermore, each user has a different leg shape, and braking is thus achieved for different rotation angles for an equal rod length.
Said rod also acts and presses in the malleolar region, and this can cause discomfort or produce accidental impacts.
Finally, considerable wheel wear is observed.
U.S. Pat. No. 4,275,895 discloses a brake for skates with two mutually parallel pairs of wheels which acts at the rear wheels.
Said brake is constituted by a flap associated with the shoe in a rearward position; a blade is associated in a rearward position with said flap and is pivoted at the supporting frame of the shoe.
Said blade has, at its free end, a transverse element on which two C-shaped elements are formed at the lateral ends; said elements interact, following a backward rotation applied to the flap, with the rear wheels facing said elements, so as to interact with the rolling surface of said wheels.
However, even this solution has drawbacks: it is in fact structurally complicated and therefore difficult to industrialize; it also entails the presence of adapted springs for repositioning the flap in the condition in which the two C-shaped elements do not interact with the wheels, thus further increasing structural complexity.
Furthermore, the structural configuration of the brake causes the two C-shaped elements to interact with the wheel even upon a minimal backward rotation applied to the flap and therefore even for involuntary movements; this produces unwanted braking actions and, accordingly, possible loss of balance or lack of coordination.
Finally, the interaction of the C-shaped element at the rolling surface of the wheels leads to their rapid wear and therefore to non-optimum rolling, which necessarily leads to continuous replacement of said wheels.
U.S. Pat. No. 4,300,781 discloses a braking device for skates that comprise pairs of mutually parallel wheels.
Accordingly, there is a brake constituted by a blade that is pivoted transversely at the rear end of the supporting frame for a shoe; pads are associated with the ends of said blade and face the rolling surface of the pair of rear wheels.
The brake is operated by using a cable to rotate the blade in contrast with a spring associated with the support for the pair of front wheels, so as to move the pads into contact with the rolling surface of the pair of rear wheels.
Said cable is activatable by means of rings or handles associated with a band that can be placed on the user's legs by temporary connection means.
However, this embodiment has considerable drawbacks; first of all, brake activation can lead to possible loss of balance during sports practice, since the body of the user does not assume a position suitable to control the sudden speed reduction; only the skater's hand is in fact involved in the activation of the brake.
Furthermore, as sports practice can occur while wearing trousers, when traction is applied to the rings the band may slip along the trousers or drag them so that they slide along the leg, hindering the braking action.
Furthermore, there is a loose cable that in addition to being a hindrance for the skater, can accidentally catch during racing, especially since coordination of the arm-leg movement moves the legs rhythmically laterally outwards.
U.S. Pat. No. 4,033,596 discloses a roller-ski having, in addition to engagement means for the tip of a shoe, braking means essentially constituted by a bar that protrudes above a supporting frame for the shoe in the rear region thereof, said bar being pivoted transversely to said frame at one end and having, at the other end, a curved plate for supporting the the user's calf.
A frame is associated transversely and to the rear of the bar; once the bar has been rotated backwards, said frame interacts with the rolling surfaces of a pair of wheels in turn freely pivoted to the supporting frame for the shoe.
If using this solution for roller skates, there would be severe drawbacks due to the fact that the sport practiced with a skate entails continuous oscillations of the leg that can lead to unwanted activations of the braking action.
Moreover, the presence of the bar would be dangerous for the user, since it constitutes a blunt body completely independent of the leg which might therefore be dangerous in case of a fall.
Furthermore, the described embodiment does not allow to achieve a gradual braking action.
U.S. Pat. No. 5,388,844 granted on Feb. 14, 1995 discloses a braking device, particularly for skates, comprising a shoe composed of a quarter that is articulated to a shell associated with a supporting frame for one or more wheels.
Said device comprises at least one rod member connected to the quarter and slideable with respect to the shell, said rod member having a fork-like end that interacts with one or more of the wheels beyond a preset backward rotation angle of the quarter.
Although this embodiment is undoubtedly an improvement and is valid, it has some small drawbacks related to the fact that it is not possible to easily achieve good graduality in the braking action, since this is mainly entrusted to the user's skill and sensitivity.